Climate change is increasing the intensity, frequency, and severity of extreme heat events (IPCC 2023).
Impacts on fertility are understudied relative to other demographic processes but link directly to climate projections (Grace 2017; Kuehn & McCormick 2017; Sellers & Gray 2019).
Low-income, tropical countries face a triple burden (Grace 2017; Potts & Henderson 2012):
Climate vulnerability
High population growth
Poor with weak health systems
Evidence on heat & fertility relationship
Extreme heat exposure adversely impacts pregnancy outcomes, such as preterm birth, low birthweight, and miscarriages (Conte Keivabu et al. 2022; Davenport et al. 2020; Kuehn & McCormick 2017; Beltran et al. 2013)
Extreme heat reduces (Sellers & Gray 2019) or delays (Barreca et al. 2018) births in some contexts
Fertility preferences also impacted by heat exposure (Sellers & Gray 2019; Eissler et al. 2019)
Gaps and methodological issues
Many studies identify potential biological and behavioral pathways: